This week a jury in Liverpool convicted two teenagers of the murder of another. The case received a huge amount of coverage. But why is the murder of Anthony Walker worthy of such publicity when others aren't?

And are some critics right to say that BBC News is shy of reporting the "racist" murders of white people? How are the decisions made about which murders to cover? NewsWatch asked TV newsgathering editor Jon Williams to respond:

The killers of Anthony Walker have been told they must serve minimum terms of 17 and 24 years

Every week in England and Wales, more than a dozen people die in suspicious circumstances. In 2003/4 (the last year for which figures are available), the Home Office recorded 853 cases of homicide: murder, manslaughter and infanticide.

Most of the victims are known to their killers - only a few are genuinely newsworthy. The Anthony Walker case was one of them; an 18 year old boy killed with an axe in an unprovoked attack. Anthony was black. His killers were white.

What made the story front page news - and the lead story on radio and television - was not his tragic death, but the claim by police, prosecution and the boy's family that the killing was racially motivated. In 2004/5, just 4 cases of homicide were classed by the Crown Prosecution Service as "racist incidents".

The facts of Anthony Walker's murder are worth repeating. The teenager had been escorting his girlfriend home when he was the victim of racial abuse. Anthony refused to be drawn and walked away. Liverpool Crown Court heard how his attacker then left, went and found an axe, and chased and killed the teenager, leaving the axe embedded in his skull.

Richard Whelan was stabbed by a black man who had been throwing chips at passengers on a bus

So the case of Anthony Walker was particularly shocking - and because of the racist motive, highly unusual. It merited the prominent coverage it received.

What's more complicated, is judging how much coverage other stories deserve.

In the same week as the black teenager was killed by two white men in Liverpool, a white man was stabbed to death by a black man on a London bus. Richard Whelan was also the victim of an unprovoked attack - killed in the prime of his life. The story was covered by BBC London and on BBC News 24.

But there was - and is - no suggestion that the attack was racially motivated. Indeed, the police made the point that the victim could have been "any one of us on a night out".

A week before Michael Barton and Paul Taylor were convicted of Anthony Walker's murder, three Asian men were jailed for life for killing a 30 year old man in East London last year. Christopher Yates was in the wrong place at the wrong time. He'd been walking home after a friend's birthday 12 months ago, when he was attacked by Zahid Bashir, Imran Maqsood and Sajid Zulfiqar.

Not racist

Witnesses said one of the men had laughed and joked about killing a white man. But the judge said it hadn't been a racist crime.

Again, the story was newsworthy. When the three men were jailed at the Old Bailey, we covered the story on both the Six and the Ten O'Clock News. While the murder was horrific and a tragedy for Christopher's family, it was one of the 853 homicides recorded by the Home Office, rather than one of the four racially motivated killings registered by the Crown Prosecution Service.

The distinction begins to explain the difference in coverage.

News coverage is driven by the judgements made by journalists, every minute of every day. No two days are the same. The "newsworthiness" of a story is governed by what else is around on the same day.

In December 2002, three Asian men were convicted of murdering Ross Parker, a Cambridgeshire teenager, in what the judge did describe as a racist killing.

The parallels with the murder of Anthony Walker are stark. Ross Parker has been walking home with his girlfriend when he was attacked by a gang of men. They hit him with a hammer, before stabbing him in the throat with a foot-long knife.

Mistake

By any standards, it too was highly unusual and worthy of coverage. But on the same day that Shied Nazi, Ahmed Ali Aswan and Sarris Ali were jailed for the murder of Ross Parker, another murder dominated the headlines.

The uncle of Danielle Jones - a schoolgirl who disappeared in Essex -- was found guilty of killing her. The search for Danielle had been extensively covered. The conviction of Stuart Campbell closed a chapter on a continuing mystery.

Add to that the build up to the war in Iraq and Hans Blix's verdict on Iraq's weapons dossier, and you begin to see how a newsworthy story about the murder of a teenager - in appalling circumstances - might be squeezed out by other stories. In hindsight, it was a mistake not to report the case of Ross Parker more extensively.

The stabbing of Abigail Witchalls in front of her son happened in one of the safest parts of Britain

In April, a Chinese man, Mi Goa Huang Chen, was attacked by a pack of teenagers in Manchester. Again, it was an horrific murder - not because of his race, but because of the number of people involved in the crime.

A week earlier, Abigail Witchalls had been stabbed while walking her two-year-old daughter at Little Bookham in Surrey. The stabbing received - and has continued to receive extensive coverage. The murder of Mi Goa Huang Chen wasn't covered at all.

Both happened during the election campaign; the Witchalls stabbing came during a lull in the campaign; the Manchester story happened on the day after the leaders had been on Question Time - a lot of editorial time that Friday was spent exploring the implications of the PM's announcement about GPs waiting times.

Dilemmas

The stabbing of Abigail Witchalls was an extraordinary story not least because of her survival and that of her unborn child. Moreover, it happened in the safest part of the safest place in the UK. It shouldn't be a case of either or - we should probably have done both.

Journalists are only human, and like everyone else, we don't always get it right. Often the judgements we make are finely balanced - and it's right that they're scrutinised by our audiences.

We need to be transparent - not least because by being so, we allow the audience to share the dilemmas we face about the stories we cover, and those we don't.

Not every murder where the victim is from one ethnic group, and the assailant another, is racist. Thankfully murder in the UK is still relatively rare - racist murders more so. Anthony Walker was the exception rather than the rule.